Answer :

To simplify the given expression [tex]\(\frac{5^x \cdot 5^{x-1}}{4-5^{x-1}}\)[/tex], let's break down the steps systematically:

1. Simplify the Numerator:
The given numerator is [tex]\(5^x \cdot 5^{x-1}\)[/tex].

Recall the properties of exponents: [tex]\(a^m \cdot a^n = a^{m+n}\)[/tex]

Therefore:
[tex]\[ 5^x \cdot 5^{x-1} = 5^{x + (x-1)} = 5^{2x-1} \][/tex]

So, the numerator simplifies to [tex]\(5^{2x-1}\)[/tex].

2. Write Down the Denominator:
The denominator is given as [tex]\(4 - 5^{x-1}\)[/tex]. This part of the expression remains as is, as it is already in its simplest form.

3. Combine the Simplified Forms:
Now, we combine the simplified numerator and the given denominator to rewrite the expression in its simplified form.

Thus, the simplified form of the given expression becomes:
[tex]\[ \frac{5^{2x-1}}{4 - 5^{x-1}} \][/tex]

Putting it all together, the fully simplified expression is:

[tex]\[ \boxed{\frac{5^{2x-1}}{4 - 5^{x-1}}} \][/tex]